抄録
The pressure drop of water single-phase and argon-water two-phase flows in mini pipes and at sudden expansion and contraction (form losses) were investigated. Diameter of test section of mini pipes was 0.57, 0.4, 0.25 and 0.12 mm, respectively. The superficial gas velocity was 2.1 < U_g < 92.5 m/s, the superficial liquid velocity was 0.03 < U_l < 10 m/s. The two-phase friction multiplier data for D > 0.5 mm showed to be in good agreement with the conventional correlations. On the other hand, the two-phase friction multiplier data for D < 0.25 mm differed from the calculated values by the conventional correlations. New correlation of mini pipes was obtained for frictional pressure drop of gas-liquid two-phase flow. The coefficients of sudden expansion and sudden contraction in mini-pipes for the gas-water two-phase flow were proposed from the present experimental results. The experimental results were also examined through numerical simulation by a commercial code. New correlation of coefficients of form losses based on Martinelli parameter was obtained for gas-liquid two-phase flow.